9 lines
282 B
Racket
9 lines
282 B
Racket
#lang typed-scheme
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(define-type-alias number Number)
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(define-type-alias boolean Boolean)
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(define-type-alias top Any)
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(define: f : (case-lambda [number -> number] [boolean boolean -> boolean])
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(case-lambda [(#{a : number}) a]
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[(#{b : boolean} #{c : boolean}) (and b c)]))
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